Molybdenum materials have suddenly emerged or become a new generation of semiconductor materials

Recently, the Laboratory of Nanoelectronics and Structures (LANES) at the EPFL in Lausanne, Switzerland, claimed that semiconductors are made of monolayer materials called molybdenum (MoS2), or they are used to make them smaller and more energy-efficient. The electronic chip will have advantages over traditional silicon materials or fullerenes in the next generation of nanoelectronic devices. Research paper published in the January 30 issue of Nature? Nanotechnology magazine.

Molybdenum is abundant in nature and is commonly used in alloy steel or lubricating oil additives. It has not been widely studied in electronics. “It is a two-dimensional material that is very thin and easy to use in nanotechnology. It has great potential in the manufacture of microtransistors, light-emitting diodes (LEDs), solar cells, etc.” Professor Andrews of the Federal Institute of Technology of Lausanne ? Case said that they compared this material with silicon and fullerenes, which are currently used primarily for electronics and computer chips.

Compared with silicon, one of the advantages of molybdenum is its smaller size, molybdenum monolayer is two-dimensional, and silicon is a three-dimensional material. "On a 0.65-nm-thick molybdenum film, electron motion is as easy as on a two-nanometer-thick silicon film," explains Case. "But it's impossible to make a silicon film as thin as a molybdenum film. ”

Another major advantage of molybdenum is its lower energy consumption than silicon. In solid state physics, band theory describes the energy of electrons in a particular material. In semiconductors, free electrons exist between these energy bands and are called "band gaps." If the band gap is not too small or too large, some electrons can skip the band gap, which can more effectively control the electronic behavior of the material and make it easier to switch circuits.

Naturally there is a large bandgap inside the molybdenum monolayer. Although its electron mobility is poor, when using a germanium oxide gate, the mobility of a single layer of molybdenum at room temperature can be achieved. Greatly improved to reach the level of fullerene nanobelts. Fullerenes have no bandgap, and in order to make the bandgap artificially complicated on the above, the electron mobility is also reduced, or high voltage is required. Since molybdenum has a direct band gap, a single layer of molybdenum can be used to fabricate the interband channel field effect transistor, and in the steady state, the energy consumption is 100,000 times smaller than that of the conventional silicon transistor. In the fields of optoelectronics and energy capture applications, monolayer molybdenum can also be used together with fullerenes to form complementary advantages.